@article {10416, title = {Anti-transglutaminase 6 Antibody Development in Children With Celiac Disease Correlates With Duration of Gluten Exposure.}, journal = {J Pediatr Gastroenterol Nutr}, volume = {66}, year = {2018}, month = {2018 Jan}, pages = {64-68}, abstract = {

OBJECTIVES: Antibodies against transglutaminase 6 (anti-TG6) have been implicated in neurological manifestations in adult patients with genetic gluten intolerance, and it is unclear whether autoimmunity to TG6 develops following prolonged gluten exposure. We measured the anti-TG6 in children with celiac disease (CD) at the diagnosis time to establish a correlation between these autoantibodies and the duration of gluten exposure. We investigated a correlation between anti-TG6 and the presence of neurological disorders.

METHODS: Anti-TG6 (IgA/IgG) were measured by ELISA in sera of children with biopsy-proven CD and of children experiencing gastrointestinal disorders. CD patients positive for anti-TG6 were retested after 2 years of gluten-free diet (GFD).

RESULTS: We analyzed the sera of 274 CD children and of 121 controls. Anti-TG6 were detected in 68/274 (25\%) CD patients and in 19/121 (16\%) controls, with significant difference between the 2 groups (P = 0.04). None of the CD patients and of the controls testing positive for anti-TG6 were experiencing neurological disorders. Eleven of 18 (61\%) CD patients with other autoimmune diseases were positive for anti-TG6. In CD patients, a significant correlation between the gluten exposure before the CD diagnosis and anti-TG6 concentration was found (P = 0.006 for IgA; P < 0.0001 for IgG). After GFD anti-TG6 concentrations were significantly reduced (P < 0.001). No significant correlation was observed between anti-TG6 and anti-TG2 serum concentrations.

CONCLUSIONS: Anti-TG6 are more prevalent in children with untreated CD in the absence of overt neurological disorders. The synthesis of the anti-TG6 is related to a longer exposure to gluten before the CD diagnosis, and the autoimmunity against TG6 is gluten dependent and disappeared during GFD.

}, issn = {1536-4801}, doi = {10.1097/MPG.0000000000001642}, author = {De Leo, Luigina and Aeschlimann, Daniel and Hadjivassiliou, Marios and Aeschlimann, Pascale and Salce, Nicola and Vatta, Serena and Ziberna, Fabiana and Cozzi, Giorgio and Martelossi, Stefano and Ventura, Alessandro and Not, Tarcisio} } @article {1602, title = {The active Zot domain (aa 288-293) increases ZO-1 and myosin 1C serine/threonine phosphorylation, alters interaction between ZO-1 and its binding partners, and induces tight junction disassembly through proteinase activated receptor 2 activation.}, journal = {FASEB J}, volume = {25}, year = {2011}, month = {2011 Jan}, pages = {144-58}, abstract = {

Vibrio cholerae-derived zonula occludins toxin (Zot) is a multifunctional protein that reversibly disassembles intestinal tight junctions (tjs). Zot structure-function analysis has mapped this activity to aa 288-293, named AT1002. AT1002 reduced transepithelial electrical resistance across rat small intestine, ex vivo, as did Zot and its processed mature form, ΔG. AT1002 increased in vivo permeability to sugar tracers, whereas scrambled control peptides did not. Binding and barrier assays in proteinase activated receptor (PAR)(2)-expressing and PAR(2)-null cells established AT1002 activity to be PAR(2) dependent. Coincident with the increased intestinal permeability, confocal microscopy of AT1002-exposed rat intestinal IEC6 cells revealed displacement of ZO-1 and occludin from intercellular boundaries. In coimmunoprecipitation assays, AT1002 decreased ZO-1-occludin and ZO-1-claudin 1 interactions coincident with PKCα-dependent ZO-1 serine/threonine phosphorylation. Further, AT1002 increased serine phosphorylation of myosin 1C and, at the same time, transiently diminished its association with ZO-1. The COOH-terminal domain of ZO-1 was required for its association with myosin 1C. These data indicate that the NH(2)-terminal portion of active Zot contains a PAR(2)-activating motif, FCIGRL, that increases PKCα-dependent ZO-1 and myosin 1C serine/threonine phosphorylation. These modifications provoke selective disengagement of ZO-1 from its binding partners, occludin, claudin 1, and myosin 1C, coincident with opening of tjs.

}, keywords = {Amino Acid Sequence, Animals, Caco-2 Cells, Cell Line, Cells, Cultured, Cholera Toxin, Epithelial Cells, Humans, Immunoblotting, Male, Membrane Proteins, Mice, Mice, Inbred BALB C, Molecular Sequence Data, Myosins, Oligopeptides, Phosphoproteins, Phosphorylation, Protein Binding, Protein Kinase C-alpha, Rats, Rats, Wistar, Receptor, PAR-2, RNA Interference, Serine, Threonine, Tight Junctions, Zonula Occludens-1 Protein}, issn = {1530-6860}, doi = {10.1096/fj.10-158972}, author = {Goldblum, Simeon E and Rai, Usha and Tripathi, Amit and Thakar, Manjusha and De Leo, Luigina and Di Toro, Nicola and Not, Tarcisio and Ramachandran, Rithwik and Puche, Adam C and Hollenberg, Morley D and Fasano, Alessio} }